Meckel’s Diverticulum

Fig. 11.1

Intussusception in a 2-year-old child. (a) Ultrasound reveals a multilayered structure with a hyperechoic center corresponding to fatty stromal remnant of the omphalomesenteric duct. (b) Post-operative resected MD after reduction of the intussusception and eversion of the MD (Courtesy, Pr K. Chaumoitre – Pr T. Merrot)

11.3.1.2 Mesodiverticular Band

A mesodiverticular band can be responsible for strangulation and volvulus of an adjacent bowel loop or of the MD itself (Fig. 11.2). This remnant band is located at the top of the MD and is linked to the umbilicus or to any structure in the abdominal cavity or may even float freely in the peritoneal cavity. Its visualization is uncommon [1]. Imaging examinations would demonstrate a small bowel obstruction with no obvious reason or related to an associated MD diverticulitis [12].

Fig. 11.2

Twelve-year-old child. CE-CT: small bowel obstruction related to a MD volvulus. The MD is distended (yellow arrows), its wall is thickened but remains vascularized

11.3.2 Diverticulitis

This complication is mostly secondary to ulceration in relation with the presence of gastric mucosa. It has been exceptionally responsible for an associated pseudo-tumor [13].Other causes of obstruction of a MD in pediatric practice include volvulus by a mesodiverticular band, torsion around its own pedicle, Burkitt’s lymphoma [14], enterolith [15], phytobezoar [16], foreign bodies [17], and ascaris [18].

In the majority of cases, the clinical symptoms are masquerading as an acute appendicitis. Less likely melena or bloody stools may be the revealing clinical symptoms.

On ultrasound [19, 20] or on CT [6], the inflamed MD appears as a blind bowel structure with no connection to the cecum. The diverticulitis will appear either tubular or like a pouch-like structure, sometimes very large. Its wall is thickened and the amount adjacent inflammatory fat appears increased and hypervascularized (Fig. 11.3). A cystic mass is present in 50% (Fig. 11.4) of cases that may mimic a duplication cyst; in the latter, a more regular wall can usually be displayed [19]. An associated enterolith is rarely present (Fig. 11.5). The visualization of an adjacent normal appendix helps to orient the differential diagnoses. These include besides appendicitis, Crohn’s disease, complicated lymphatic malformation and whenever located close to the umbilicus, inflammation of an urachal remnant.

Fig. 11.3

Diverticulitis in a 7-year-old boy explored on CE-CT. (a) An inflamed tubular bowel structure is present on the midline (yellow arrows). (b) The tubular structure connected to the umbilicus (yellow arrow) is associated with an adjacent increased amount of fat (dashed arrows)

Fig. 11.4

Four-year-old boy complaining of acute onset of abdominal pain. US reveals a cystic structure surrounded by a hyperechoic wall (yellow arrow) and hyperechoic fatty infiltration with some free fluid (dashed yellow arrow). Surgery and histology confirmed the presence of an inflamed MD

Fig. 11.5

Meckel’s diverticulitis in a 3-year-old girl. (a) US transverse sections. US demonstrates on the right side of the umbilicus presence of an oval shape cystic structure on the antimesenteric side of an ileal loop. This lesion presents with a thick surrounding wall without bowel layer differentiation. (b) The mass is filled with fluid and contains in its distal part a hyperechoic shadowing structure corresponding to an enterolith

11.3.3 Hemorrhage

Hemorrhage is mainly secondary to peptic ulceration due to the presence of gastric mucosa within the diverticulum. Hemorrhage may also be a complication of diverticulitis. Such complications are reported to be more severe during childhood [21]; however, severe hemorrhagic presentations have been only scarcely reported [4, 22]. Tc-pertechnetate scintigraphy (Fig. 11.6) is considered as the gold standard procedure to detect gastric mucosa but its negative predictive value is low (0.74) especially when the hemoglobin level in the serum is lower than 11 g/dL [23]. In case of acute bleeding, 99mTc-erythrocytes labeled scintigraphy is described more accurate [24]. SPECT/CT is recommended to avoid false result due to the physiological uptake of the kidney. Scintigraphy can be falsely positive due to intestinal duplication cysts containing heterotopic gastric mucosa, intussusception or significant bowel wall inflammation [7]. CT and US have not proven to be useful in such presentations.

Fig. 11.6

Chronic abdominal pain secondary to MD ulceration in a 4-year-old girl. Tc-99m pertechnetate scintigraphy: A hyperintense activity is identified on the right iliac fossa corresponding to gastric mucosa uptake. (Courtesy G Petyt, MD)

11.3.4 Perforation

Perforation is exceptionally described in pediatric patients. Kotecha et al. reported multiple mechanisms for this complication such as inflammation, ulceration, ischemia, occlusion by parasites or foreign bodies, post-traumatic perforation, and volvulus [2].

11.4 Unusual Presentation

11.4.1 Littre Hernia

Littre Hernia refers to a small bowel obstruction secondary to the incarceration of a MD within a hernia. The specificity in children is the higher prevalence of the umbilical localization of the hernia (85%) [25] and a more frequent “acute” presentation than in adults. Other sites of hernia include the inguinal canal, any post-operative orifice, and even the diaphragm [26].

Only gold members can continue reading. Log In or Register to continue